Ex 13.2, 9 - Chapter 15 Class 11 Statistics (Important Question)
Last updated at May 7, 2024 by Teachoo
Chapter 15 Class 11 Statistics
Chapter 15 Class 11 Statistics
Last updated at May 7, 2024 by Teachoo
Ex15.2, 9 Find the mean, variance and standard deviation using short-cut method Mean(π₯ Μ ) = A + (ββπππ¦π)/(ββππ) Γβ where A = assumed mean = 92.5 π¦_π=(π₯_π β π΄)/β h = class size = 75 β 70 = 5 Variance (π)2 = β2/N2 [πββπππ¦π2 β (ββπππ¦π)^2 ] = 52/602 [N Γ (254) β (6)2] = 25/3600 [60 Γ254 β36] = 25/3600 Γ 15204 = 105.58 β΄ Standard deviation (π) = βVariance = β105.58 = 10.27